US20130153841A1 - Winch operated hoist and method of operating same - Google Patents
Winch operated hoist and method of operating same Download PDFInfo
- Publication number
- US20130153841A1 US20130153841A1 US13/331,600 US201113331600A US2013153841A1 US 20130153841 A1 US20130153841 A1 US 20130153841A1 US 201113331600 A US201113331600 A US 201113331600A US 2013153841 A1 US2013153841 A1 US 2013153841A1
- Authority
- US
- United States
- Prior art keywords
- elongated member
- idler pulley
- cable
- operatively
- load
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Abandoned
Links
Images
Classifications
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B66—HOISTING; LIFTING; HAULING
- B66C—CRANES; LOAD-ENGAGING ELEMENTS OR DEVICES FOR CRANES, CAPSTANS, WINCHES, OR TACKLES
- B66C23/00—Cranes comprising essentially a beam, boom, or triangular structure acting as a cantilever and mounted for translatory of swinging movements in vertical or horizontal planes or a combination of such movements, e.g. jib-cranes, derricks, tower cranes
- B66C23/18—Cranes comprising essentially a beam, boom, or triangular structure acting as a cantilever and mounted for translatory of swinging movements in vertical or horizontal planes or a combination of such movements, e.g. jib-cranes, derricks, tower cranes specially adapted for use in particular purposes
- B66C23/36—Cranes comprising essentially a beam, boom, or triangular structure acting as a cantilever and mounted for translatory of swinging movements in vertical or horizontal planes or a combination of such movements, e.g. jib-cranes, derricks, tower cranes specially adapted for use in particular purposes mounted on road or rail vehicles; Manually-movable jib-cranes for use in workshops; Floating cranes
- B66C23/44—Jib-cranes adapted for attachment to standard vehicles, e.g. agricultural tractors
Definitions
- This invention relates generally to hoists and more particularly to a winch operated hoist.
- U.S. Pat. No. 6,152,675 to Compton shows a winch operated hoist of a type designed to attach to a vehicle receiver hitch.
- the distance that a load to be lifted in this type of a device is limited by the length of a vertical post that extends upwardly, though Compton uses a two piece vertical post that permits the length of the vertical post to be adjustable by manually telescoping the inside post up and pinning it to a desired height using holes in the two piece post and using a pin through aligned holes in the adjusting process.
- This manual adjusting process is manageable but with one person may be difficult to lift the inside post to align the holes in the inner and outer tubes and then placing a pin through the aligned holes.
- FIG. 1 is a side view of a hoist constructed in accordance with the present invention shown in preparation for lifting a load;
- FIG. 2 is a side elevational view, like FIG. 1 , but showing the hoist having lifted the load through a first stage;
- FIG. 3 is a side elevational view, like FIGS. 1 and 2 , but showing a second stage of lifting from FIG. 2 wherein a second elongated tube member is caused to move up due to a winch and idler pulley system, showing partial movement upwardly of the inner elongated tube in solid lines and even more movement upwardly of the inner elongated is shown in dashed lines as the winch is used to wrap more cable onto the reel thereof and also shows in dashed lines pivoting a horizontal beam by one hundred and eighty degrees;
- FIG. 4 is an enlarged cross sectional view taken at the circle 4 of FIG. 3 ;
- FIG. 5 is an enlarged cross sectional view taken at the circle 5 of FIG. 3 ;
- FIG. 6 is an enlarged cross sectional view taken at the circle 6 of FIG. 3 ;
- FIG. 7 is a side elevational view like FIG. 3 in the raised and pivoted position in dashed lines, and showing the load being lowered by letting the cable unwind off of the reel of the winch.
- FIG. 8 is an exploded cross sectional view similar to the cross sectional view of FIG. 6 to show the details of how a bushing is used to allow the horizontal third beam to pivot about a vertical axis;
- FIG. 8A is a view taken along line 8 A- 8 A of FIG. 8 ;
- FIG. 8B is a view taken along line 8 B- 8 B of FIG. 8 .
- FIG. 1 shows a hoist 10 constructed in accordance with the present invention.
- a frame 11 is shown telescoping into a receiver hitch tube 12 of a vehicle 13 in the conventional way a ball hitch would be attached to the receiver 12 of a vehicle 13 , using a pin 12 a that passes through aligned holes in the receiver 12 and frame 11 to hold the frame 11 securely attached to the vehicle 13 .
- a first elongated steel tube member 14 is rigidly attached to the frame 11 and has a second elongated steel tube member 15 telescopingly disposed inside of the first elongated steel tube member 14 .
- a third elongated steel member 16 which is preferably a U-shaped member but can be of other configurations, is pivotally mounted to the top of the second elongated steel tube member 15 via a bushing 17 as can best be seen in FIGS. 6 and 8 . This allows the elongated steel U-shaped member 16 to pivot about a vertical axis between the two positions shown in FIG. 3 in dashed lines and can in fact pivot three hundred sixty five degrees about the vertical axis of tube 15 .
- An electric winch 20 shown in FIGS. 1-3 and 7 is operatively attached to the frame 11 , or to the first elongated steel tube member 14 , or both.
- This winch 20 does not need to be electrically operated, but could be operated with a hand crank or hydraulically, for example.
- the winch 20 has a reel 21 shown in dashed lines.
- the reel 21 is shown rotatable about a horizontal axis.
- One end of a cable 22 is attached to the reel 22 of the winch 20 .
- the other end of the cable 22 has a hook 23 attached thereto.
- the cable 22 of the winch 20 is trained over an idler pulley 30 that is rotatably attached to the top of the first elongated steel tube member 14 , then under a second idler pulley 31 that is rotatably attached to the bottom of the second elongated steel tube member 15 .
- the cable 22 is then trained over the top of a third idler pulley 32 , the third idler pulley 32 being rotatably attached to the third elongated member 16 and then over a second idler pulley 33 that is also rotatably attached to the third elongated steel member 16 .
- FIGS. 6 , 8 and 8 B show an outer bushing 35 welded or otherwise fastened rigidly to the inner steel tube 15 .
- An inner bushing 36 has an intermediate annular flange 36 f between a top cylindrical part 36 t and a bottom cylindrical part 36 b.
- the bottom cylindrical part 36 b of the inner bushing 36 slides into the outer bushing 35 so it can rotate with respect to the outer bushing
- the upper part of the inner bushing 36 t slides into a notch formed in the horizontal arm 16 and the flange 36 f is welded or otherwise fastened to the horizontal arm 16 as can be seen by weld 36 w in FIG. 6 so that the inner bushing is fixed with respect to arm 16 and can pivot with respect to the outer bushing 35 to allow the horizontal arm 16 to pivot about a vertical axis coincident with the vertical axis of in inner bushing 36 and the outer bushing 35 .
- the winch 20 would be used to attach to a load 40 by letting out enough cable 22 so the hoist 10 would be in the configuration shown in FIG. 1 with the third elongated steel member/arm 16 effectively in abutment with the top of the first elongated steel tube member 14 though the actual structure at this joint is shown in FIGS. 6 and 8 .
- the winch 20 is used to wind the cable 22 onto the reel 21 as shown in FIG. 2 to lift the load 40 until the hook 23 hits the idler pulley 33 at the free end of the elongated steel member/arm 16 .
- a stop block 39 rigidly attached to the inner tube 15 will abut the upper idler pulley 30 as the inner tube 15 moves upwardly and the inner tube 15 will stop moving upwardly once the stop block hits the idler pulley 30 corresponding to the extreme upper position of the inner tube 15 and horizontal arm 16 shown in dashed lines in FIG. 3 .
- the elongated steel member/arm 16 can be pivoted by hand to the right side position shown in FIG. 3 if desired to drop the load 40 on the right side of the inner and outer tubes 15 and 14 respectively, or at any pivoted position 360 degrees around the vertical axis of the bushings 35 and 36 ( FIGS. 6 and 8 .)
- FIG. 7 shows that slowly unwinding the cable 22 from the winch 20 will allow the load 40 to be lowered as much as is desired, for example to a top of the vehicle, not shown.
- the entire operation can then be repeated with a second load 40 by reversing and then repeating the process just explained above, i.e. raise the hook 23 , manually pivoting the elongated steel member/arm 16 to the FIG. 3 position, lowering the elongated steel member/arm 16 to the FIG. 1 position, hooking on the new load 40 , etc.
- FIG. 8B shows how member 35 is welded to tubular member 15 at weld 35 w.
- the present invention 10 can be used in other places than just attached to the receiver hitch 12 of a vehicle 13 .
- the invention 10 is quite useful at construction sites where materials need to be moved to one or more higher levels or stories of a building and is extremely useful for constructing log homes where the logs need to be lifted from a truck to the elevated locations where needed.
- the hoist 10 can be moved from one level of a log home under construction to the next higher level as the home is being built until it is at the roof level where roofing materials can also be elevated until all of the parts of the building or home have been lifted to the height needed for such construction project.
- the aforementioned substrate 200 can be molded to include some or all of the aforementioned channels.
- the aforementioned algorithm can be normalized as desired over a given length or total range and can be customized for essentially any angle, frequency, or line spacing as may be desired.
Abstract
A winch operated hoist has a first elongated vertical member is operatively attached at a lower end thereof to a frame. A second elongated vertical member telescopically disposed in the first elongated member. A third elongated member operatively attached to a top end of the second elongated member, the third elongated member being perpendicular to the second elongated member, the third elongated member being operatively pivotally disposed with respect to the first elongated member about a substantially vertical axis. Using a series of idler pulleys, over which a cable of the winch is trained, the second elongated member telescopes up to raise a load higher than it could be lifted using prior art technology.
Description
- This invention relates generally to hoists and more particularly to a winch operated hoist.
- Hoists of various kinds are known in the art. For example, U.S. Pat. No. 6,152,675 to Compton shows a winch operated hoist of a type designed to attach to a vehicle receiver hitch. The distance that a load to be lifted in this type of a device is limited by the length of a vertical post that extends upwardly, though Compton uses a two piece vertical post that permits the length of the vertical post to be adjustable by manually telescoping the inside post up and pinning it to a desired height using holes in the two piece post and using a pin through aligned holes in the adjusting process. This manual adjusting process is manageable but with one person may be difficult to lift the inside post to align the holes in the inner and outer tubes and then placing a pin through the aligned holes.
- Accordingly, there is a need for a more automatic way to provide a hoist of the Compton type which does not require manual adjusting of the main vertical post in order to lift a load higher than the length of the main vertical post of the hoist.
- The above needs are at least partially met through provision of the method and apparatus described in the following detailed description, particularly when studied in conjunction with the drawings, wherein:
-
FIG. 1 is a side view of a hoist constructed in accordance with the present invention shown in preparation for lifting a load; -
FIG. 2 is a side elevational view, likeFIG. 1 , but showing the hoist having lifted the load through a first stage; -
FIG. 3 is a side elevational view, likeFIGS. 1 and 2 , but showing a second stage of lifting fromFIG. 2 wherein a second elongated tube member is caused to move up due to a winch and idler pulley system, showing partial movement upwardly of the inner elongated tube in solid lines and even more movement upwardly of the inner elongated is shown in dashed lines as the winch is used to wrap more cable onto the reel thereof and also shows in dashed lines pivoting a horizontal beam by one hundred and eighty degrees; -
FIG. 4 is an enlarged cross sectional view taken at the circle 4 ofFIG. 3 ; -
FIG. 5 is an enlarged cross sectional view taken at the circle 5 ofFIG. 3 ; -
FIG. 6 is an enlarged cross sectional view taken at the circle 6 ofFIG. 3 ; and -
FIG. 7 is a side elevational view likeFIG. 3 in the raised and pivoted position in dashed lines, and showing the load being lowered by letting the cable unwind off of the reel of the winch. -
FIG. 8 is an exploded cross sectional view similar to the cross sectional view ofFIG. 6 to show the details of how a bushing is used to allow the horizontal third beam to pivot about a vertical axis; -
FIG. 8A is a view taken alongline 8A-8A ofFIG. 8 ; and -
FIG. 8B is a view taken alongline 8B-8B ofFIG. 8 . - Elements in the Figures are illustrated for simplicity and clarity and have not necessarily been drawn to scale. For example, the dimensions and/or relative positioning of some of the elements in the Figures may be exaggerated relative to other elements to help to improve understanding of various embodiments of the present invention. Also, common but well-understood elements that are useful or necessary in a commercially feasible embodiment are often not depicted in order to facilitate a less obstructed view of these various embodiments of the present invention. Certain actions and/or steps may be described or depicted in a particular order of occurrence while those skilled in the art will understand that such specificity with respect to sequence is not actually required. The terms and expressions used herein have the ordinary technical meaning as is accorded to such terms and expressions by persons skilled in the technical field as set forth above except where different specific meanings have otherwise been set forth herein.
- Referring now to the drawings wherein like reference numerals designate identical or corresponding parts throughout the several views,
FIG. 1 shows ahoist 10 constructed in accordance with the present invention. A frame 11 is shown telescoping into areceiver hitch tube 12 of avehicle 13 in the conventional way a ball hitch would be attached to thereceiver 12 of avehicle 13, using apin 12 a that passes through aligned holes in thereceiver 12 and frame 11 to hold the frame 11 securely attached to thevehicle 13. - Referring now to
FIGS. 1-3 , a first elongatedsteel tube member 14 is rigidly attached to the frame 11 and has a second elongatedsteel tube member 15 telescopingly disposed inside of the first elongatedsteel tube member 14. A thirdelongated steel member 16, which is preferably a U-shaped member but can be of other configurations, is pivotally mounted to the top of the second elongatedsteel tube member 15 via a bushing 17 as can best be seen inFIGS. 6 and 8 . This allows the elongatedsteel U-shaped member 16 to pivot about a vertical axis between the two positions shown inFIG. 3 in dashed lines and can in fact pivot three hundred sixty five degrees about the vertical axis oftube 15. - An
electric winch 20 shown inFIGS. 1-3 and 7 is operatively attached to the frame 11, or to the first elongatedsteel tube member 14, or both. Thiswinch 20 does not need to be electrically operated, but could be operated with a hand crank or hydraulically, for example. Thewinch 20 has areel 21 shown in dashed lines. Thereel 21 is shown rotatable about a horizontal axis. One end of acable 22 is attached to thereel 22 of thewinch 20. The other end of thecable 22 has ahook 23 attached thereto. - The
cable 22 of thewinch 20 is trained over anidler pulley 30 that is rotatably attached to the top of the first elongatedsteel tube member 14, then under asecond idler pulley 31 that is rotatably attached to the bottom of the second elongatedsteel tube member 15. Thecable 22 is then trained over the top of athird idler pulley 32, thethird idler pulley 32 being rotatably attached to the thirdelongated member 16 and then over asecond idler pulley 33 that is also rotatably attached to the thirdelongated steel member 16. -
FIGS. 6 , 8 and 8B show anouter bushing 35 welded or otherwise fastened rigidly to theinner steel tube 15. Aninner bushing 36 has an intermediateannular flange 36 f between a topcylindrical part 36 t and a bottom cylindrical part 36 b. The bottom cylindrical part 36 b of theinner bushing 36 slides into theouter bushing 35 so it can rotate with respect to the outer bushing The upper part of theinner bushing 36 t slides into a notch formed in thehorizontal arm 16 and theflange 36 f is welded or otherwise fastened to thehorizontal arm 16 as can be seen byweld 36 w inFIG. 6 so that the inner bushing is fixed with respect toarm 16 and can pivot with respect to theouter bushing 35 to allow thehorizontal arm 16 to pivot about a vertical axis coincident with the vertical axis of ininner bushing 36 and theouter bushing 35. - In operation the
winch 20 would be used to attach to aload 40 by letting outenough cable 22 so thehoist 10 would be in the configuration shown inFIG. 1 with the third elongated steel member/arm 16 effectively in abutment with the top of the first elongatedsteel tube member 14 though the actual structure at this joint is shown inFIGS. 6 and 8 . - Then the
winch 20 is used to wind thecable 22 onto thereel 21 as shown inFIG. 2 to lift theload 40 until thehook 23 hits theidler pulley 33 at the free end of the elongated steel member/arm 16. - Continuing to use the
winch 20 by using theelectronic switch controller 24 shown inFIG. 3 towind cable 22 onto the reel from the position shown inFIG. 2 will cause theload 40 to continue to move upwardly as shown inFIG. 3 because thecable 22 will force thelower idler pulley 31 to move upwardly as thecable 22 is shortened, thereby forcing theinner tube 15 and elongated steel member/arm 16 upwardly first to the intermediate position shown in solid lines inFIG. 3 , and, with continued reeling in of thecable 22 will cause theload 40 to move upwardly to the dashed lined position shown inFIG. 3 , on the left side ofFIG. 3 . - It is noted that a
stop block 39 rigidly attached to theinner tube 15 will abut theupper idler pulley 30 as theinner tube 15 moves upwardly and theinner tube 15 will stop moving upwardly once the stop block hits theidler pulley 30 corresponding to the extreme upper position of theinner tube 15 andhorizontal arm 16 shown in dashed lines inFIG. 3 . Once theload 40 is at that extreme top position shown in dashed lines inFIG. 3 , the elongated steel member/arm 16 can be pivoted by hand to the right side position shown inFIG. 3 if desired to drop theload 40 on the right side of the inner andouter tubes bushings 35 and 36 (FIGS. 6 and 8 .) -
FIG. 7 shows that slowly unwinding thecable 22 from thewinch 20 will allow theload 40 to be lowered as much as is desired, for example to a top of the vehicle, not shown. The entire operation can then be repeated with asecond load 40 by reversing and then repeating the process just explained above, i.e. raise thehook 23, manually pivoting the elongated steel member/arm 16 to theFIG. 3 position, lowering the elongated steel member/arm 16 to theFIG. 1 position, hooking on thenew load 40, etc. -
FIG. 8B shows howmember 35 is welded totubular member 15 atweld 35 w. - It is to be understood that the
present invention 10 can be used in other places than just attached to thereceiver hitch 12 of avehicle 13. For example theinvention 10 is quite useful at construction sites where materials need to be moved to one or more higher levels or stories of a building and is extremely useful for constructing log homes where the logs need to be lifted from a truck to the elevated locations where needed. Thehoist 10 can be moved from one level of a log home under construction to the next higher level as the home is being built until it is at the roof level where roofing materials can also be elevated until all of the parts of the building or home have been lifted to the height needed for such construction project. - Those skilled in the art will recognize that a wide variety of modifications, alterations, and combinations can be made with respect to the above described embodiments without departing from the spirit and scope of the invention, and that such modifications, alterations, and combinations are to be viewed as being within the ambit of the inventive concept. As one illustrative example in these regards, the aforementioned substrate 200 can be molded to include some or all of the aforementioned channels. As another illustrative example in these regards, the aforementioned algorithm can be normalized as desired over a given length or total range and can be customized for essentially any angle, frequency, or line spacing as may be desired.
Claims (8)
1. A winch operated hoist comprising:
a frame;
a first elongated member operatively attached at a lower end thereof to the frame;
a second elongated member telescopically disposed in the first elongated member;
a third elongated member operatively attached to a top end of the second elongated member, the third elongated member being disposed transversely with respect to the second elongated member, the third elongated member being operatively pivotally disposed with respect to the first elongated member about a substantially vertical axis;
a winch operatively attached to at least one of the frame and first elongated member, the winch having a reel with a flexible cable having one end thereof operatively attached thereto and the other end being a free end;
a first idler pulley operatively rotatably attached to a top portion of the first elongated member;
a second idler pulley operatively rotatably attached to a bottom portion of the second elongated member;
a third idler pulley operatively rotatably attached to a first portion of the third elongated member;
a fourth idler pulley operatively rotatably attached to a second portion of the third elongated member, the fourth idler pulley being spaced a distance farther from the first elongated member than the distance of the third idler pulley is from the first elongated member;
the cable being trained over the first idler pulley, under the second idler pulley and over the third and fourth idler pulleys; and
the free end of the cable being adapted to attach a load to be lifted thereto.
2. The winch operated hoist of claim 1 wherein the second elongated member is operatively pivotally attached to a top end of the first elongated member.
3. The winch operated hoist of claim 1 wherein the first elongated member is a tube and the second elongated member is at least partially disposed within the first elongated member.
4. The winch operated hoist of claim 1 wherein a stop operatively attached to the second elongated member limits the extent that the second elongated member will extend above the top of the first elongated member.
5. The winch operated hoist of claim 1 wherein the second elongated member is a tubular member.
6. The winch operated hoist of claim 1 wherein the free end of the cable has a hook thereon for selective attachment to a load to be lifted.
7. A method of using a winch operated hoist of a type comprising
a frame;
a first elongated member operatively attached at a lower end thereof to the frame;
a second elongated member telescopically disposed in the first elongated member;
a third elongated member operatively attached to a top end of the second elongated member, the third elongated member being disposed transversely with respect to the second elongated member, the third elongated member being operatively pivotally disposed with respect to the first elongated member about a substantially vertical axis;
a winch operatively attached to at least one of the frame and first elongated member, the winch having a reel with a flexible cable having one end thereof operatively attached thereto and the other end being a free end; a first idler pulley operatively rotatably attached to a top portion of the first elongated member;
a second idler pulley operatively rotatably attached to a bottom portion of the second elongated member;
a third idler pulley operatively rotatably attached to a first portion of the third elongated member;
a fourth idler pulley operatively rotatably attached to a second portion of the third elongated member, the fourth idler pulley being spaced a distance farther from the first elongated member than the distance of the third idler pulley is from the first elongated member;
the cable being trained over the first idler pulley, under the second idler pulley and over the third and fourth idler pulleys;
and the free end of the cable being adapted to attach a load to be lifted thereto, said method comprising:
attaching the free end of the cable to a load;
turning the reel of the winch in one rotary direction to cause the cable to wind onto the reel until the load is lifted off of the ground;
continuing to rotate the reel in the one rotary direction until the free end of the cable stops with respect to the fourth idler pulley;
continuing to rotate the reel in the one rotary direction until the second and third elongated members and the load are raised to a desired level due to the second elongated member moving upwardly with respect to the first elongated member;
pivoting the third elongated member along a vertical axis until the load is above a place where it is desired to place the load;
reversing the rotary direction of the reel of the winch to allow the cable to be unwound from the reel whereby the second and third elongated members and the load will be lowered to the place where the load is desired to be placed; and
releasing the load from the free end of the cable.
8. The method of claim 7 further comprising:
pivoting the third elongated member along a vertical axis;
continuing to turn the reel in said reversed direction to cause the cable to unwind off of the reel until the second elongated member lowers with respect to the first elongated member and the free end of the cable is at a level low enough to be attached to a second load; and
repeating the steps of claim 7 to move the second load to an elevated place.
Priority Applications (1)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
US13/331,600 US20130153841A1 (en) | 2011-12-20 | 2011-12-20 | Winch operated hoist and method of operating same |
Applications Claiming Priority (1)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
US13/331,600 US20130153841A1 (en) | 2011-12-20 | 2011-12-20 | Winch operated hoist and method of operating same |
Publications (1)
Publication Number | Publication Date |
---|---|
US20130153841A1 true US20130153841A1 (en) | 2013-06-20 |
Family
ID=48609191
Family Applications (1)
Application Number | Title | Priority Date | Filing Date |
---|---|---|---|
US13/331,600 Abandoned US20130153841A1 (en) | 2011-12-20 | 2011-12-20 | Winch operated hoist and method of operating same |
Country Status (1)
Country | Link |
---|---|
US (1) | US20130153841A1 (en) |
Cited By (1)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US9604825B2 (en) | 2014-02-12 | 2017-03-28 | Andrew Avila | Hoist device and method |
-
2011
- 2011-12-20 US US13/331,600 patent/US20130153841A1/en not_active Abandoned
Cited By (1)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US9604825B2 (en) | 2014-02-12 | 2017-03-28 | Andrew Avila | Hoist device and method |
Similar Documents
Publication | Publication Date | Title |
---|---|---|
US10106946B2 (en) | Pile upending system | |
US7810574B2 (en) | Submersible pump puller and method of use | |
US20120241403A1 (en) | Anti-two block system for a crane assembly | |
US9140025B2 (en) | Long travel lift system | |
AU2013201258A1 (en) | A cable dispensing apparatus | |
CN113966310B (en) | Self-lifting crane system and method for lifting self-lifting crane | |
US8584827B1 (en) | Swing hopper mover including means to lift the same to a transport position | |
US20130153841A1 (en) | Winch operated hoist and method of operating same | |
JP2007089514A (en) | Automatically foldable extensible frost protection fan apparatus | |
CN106553968A (en) | It is a kind of can on-load luffing lifting arm elevator apparatus | |
US20130259609A1 (en) | Truss lifter and stabilizer | |
JP7394077B2 (en) | Large crane with boom | |
JP6628310B2 (en) | Derrick for steel tower assembly and dismantling | |
US10464788B1 (en) | Portable hoisting system | |
CN106542444A (en) | A kind of moment of flexure reduction structure set up in tower body revolution | |
CN206466915U (en) | A kind of jack up fixes the pitching luffing boom device of tower crane | |
JP2001040663A (en) | Method and device for erecting leader for pile driver | |
US1092096A (en) | Extensible tower. | |
CA2686295C (en) | Guide tube for continuous rod | |
US4651884A (en) | Portable and collapsible derrick structure | |
KR20220095550A (en) | Apparatus for lifting and lowering objects | |
US20220315393A1 (en) | Portable Hoisting System | |
US4615450A (en) | Portable and collapsible derrick structure | |
CN117188820B (en) | Construction method for installing protection overhanging platform on outer layer of building and hoisting system | |
US20230220729A1 (en) | Load lifting system |
Legal Events
Date | Code | Title | Description |
---|---|---|---|
STCB | Information on status: application discontinuation |
Free format text: ABANDONED -- FAILURE TO RESPOND TO AN OFFICE ACTION |